Calculate your monthly electricity bill from appliance wattage, usage hours, and rate. Free online electricity cost calculator with formula, examples, and FAQ.
The electricity bill calculator helps you estimate the cost of running any electrical appliance based on its wattage, daily usage, and your utility rate. Understanding your electricity consumption is the first step toward reducing energy costs and making informed decisions about appliance usage and upgrades.
kWh/Day = (Wattage ÷ 1000) × Hours Per Day
kWh/Month = kWh/Day × Days Per Month
Monthly Bill = kWh/Month × Rate Per kWhKilowatt-hours (kWh) is the standard unit for measuring electricity consumption. One kWh equals 1,000 watts running for one hour. The cost is calculated by multiplying the total kWh consumed by your utility rate per kWh. Your utility rate can be found on your electricity bill.
| Input | Output |
|---|---|
| 100W bulb, 8 hrs/day, 30 days, $0.12/kWh | Monthly: 24 kWh, $2.88/month, $34.56/year |
| 1500W heater, 6 hrs/day, 30 days, $0.15/kWh | Monthly: 270 kWh, $40.50/month, $486.00/year |
| 500W fridge, 24 hrs/day, 30 days, $0.10/kWh | Monthly: 360 kWh, $36.00/month, $432.00/year |